x86: Introduce 'struct fpu' and related API
Currently all fpu state access is through tsk->thread.xstate. Since we wish
to generalize fpu access to non-task contexts, wrap the state in a new
'struct fpu' and convert existing access to use an fpu API.
Signal frame handlers are not converted to the API since they will remain
task context only things.
Signed-off-by: Avi Kivity <avi@redhat.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1273135546-29690-3-git-send-email-avi@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c
index 28ad9f4..f18fd9c 100644
--- a/arch/x86/kernel/process.c
+++ b/arch/x86/kernel/process.c
@@ -32,25 +32,22 @@
int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)
{
+ int ret;
+
*dst = *src;
- if (src->thread.xstate) {
- dst->thread.xstate = kmem_cache_alloc(task_xstate_cachep,
- GFP_KERNEL);
- if (!dst->thread.xstate)
- return -ENOMEM;
- WARN_ON((unsigned long)dst->thread.xstate & 15);
- memcpy(dst->thread.xstate, src->thread.xstate, xstate_size);
+ if (fpu_allocated(&src->thread.fpu)) {
+ memset(&dst->thread.fpu, 0, sizeof(dst->thread.fpu));
+ ret = fpu_alloc(&dst->thread.fpu);
+ if (ret)
+ return ret;
+ fpu_copy(&dst->thread.fpu, &src->thread.fpu);
}
return 0;
}
void free_thread_xstate(struct task_struct *tsk)
{
- if (tsk->thread.xstate) {
- kmem_cache_free(task_xstate_cachep, tsk->thread.xstate);
- tsk->thread.xstate = NULL;
- }
-
+ fpu_free(&tsk->thread.fpu);
WARN(tsk->thread.ds_ctx, "leaking DS context\n");
}